This article provides steps to enable serial-line logging for an ESXi 5.0 host.
It is sometimes helpful to have logs captured independent of disk or network connectivity when troubleshooting issues. Enabling serial logging sends all VMkernel logs to the serial port in addition to their normal destination. For more information on network-based logs, see Configuring syslog on ESXi 5.0 (2003322). For more information on disk-based logs, see Location of ESXi 5.0 log files (2004201).
This article assumes that the ESXi host's serial port is connected to a remote computer, and that remote computer is listening for logs on the serial port. For more general information, see the parent article in this series Enabling serial-line logging for an ESX or ESXi host (1003900).
ESXi 5.0 can be configured to send logs to the serial port at three points in time:
Collect logs leading up to the time that the problem occurs.
A running ESXi host can be configured to output log messages via the serial communications port. If the ESXi host does not successfully boot, consider configuring it during startup instead.
Change four configuration options using one of the methods in Configuring advanced options for ESX/ESXi (1038578):
If an ESXi 5.0 host does not successfully boot, serial line logging can be configured using advanced kernel boot-time parameters. This takes effect for the current boot, and does not persist across future reboots.
To enable serial-line logging during startup:
> vmkBootVerbose=TRUE vmbLog=TRUE logPort=com1
> debugLogToSerial=1 logPort=com1 no-auto-partition bootUUID=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Note: Serial line logging continues until the configuration options are loaded, at which point the saved configuration takes effect. To continue serial line logging after booting, make the configuration change after installation and startup.
If an ESXi 5.0 host does not successfully install, serial line logging can be configured when booting the installer using advanced kernel boot-time parameters. This takes effect for the current boot, and does not persist across future reboots.
To enable serial-line logging during installation:
> runweasel debugLogToSerial=1 logPort=com1
Note: Configuration changes applied when starting the installer do not persist to the installed ESX configuration. To continue serial-line logging after booting, make the configuration change after installation and startup.
Based on VMware KB1033888